Reloading Rifle Rounds

[fguffey]

[MongooseV8]

1: Its common to shave the base of a die to get the shoulder where you want it.

2: Not all dies full length size the entire case, leaving room to set the shoulder where you want it. The shell holder and die dont even make contact. You can set headspace longer or shorter.

3: A die/press can and will change over time as tolerances change from repeated use. So its very probable that a die can "tighten up" over time.

4: I dont know why Im even typing this, as I know whats gonna happen.

[JagerDog]

The case will headspace on the extractor when you have extremely long headspace in a controlled feed action like Hatcher was working with.
This will let the case shoulder form to the chamber as is commonly done on wildcats.
This is usually combined with breech seating the bullets to keep the case back against the breech.

Ackley did the same experiments as Hatcher but the experiments were NOT designed to prove that cases do not slide forward in a chamber to hit the shoulder because there is normally only a few thousandths headspace but MORE extractor clearance.

I can dig out my Ackley book and scan the page if you like.
Guffey will likely tell us that Hatcher and Ackley did not know what they were doing.

Brass flows/takes the path of least resistance. Who knew?

[fguffey]

4: I dont know why Im even typing this, as I know whats gonna happen.

There is a lot of room for someone to get involved but it sounds like you have got it the way you want it.

F. Guffey

[JagerDog]

What guffster is trying to explain was a question nobody asked or eluded to in order to sound (to himself) intelligent. Namely fire-forming parent brass to a modified (roomy) chamber. As the pressure builds, the brass will attempt to fill the chamber. Physics doesn't care where the brass comes from. It can stretch the body/shoulder brass (making it thinner). It can draw back the mouth. Water takes the shape of the bucket containing it. Increase the diameter of the bucket and the column height will become shorter. Visualize brass flowing as similar. You're not going to compress either.

Typically this is done with greatly reduced loads, with fast burning powder and a filler such a Cream of Wheat. Feel free to google "cream of wheat method". This creates enough pressure to reform the brass to the new chamber. Typically done when "wildcatting" or to obtain brass for calibers which are difficult/expensive to find.

In "normal" operation of RELOADING, the primary growth in case length comes while reforming the shoulder to provide the proper amount of clearance in the chamber. A common term is "bumping" the shoulder back. Guffster finds fault with the term as you aren't actually taking the exact same material in the shoulder and relocating it towards the case head. The case material "flows" under the pressure of the die. The easiest place for excess material to go is further into the die, lengthening the case. This is why you check/trim case length AFTER you resize.

Somewhat fascinating if so inclined, but really rather meaningless to most. Best practice is to resize ("bump" the shoulder) just enough to provide reliable feeding/chambering. This will forestall the eventual thinning of the brass in critical areas. Oversized chambers (often found in machine guns) will exaggerate the phenomenon, especially if returning the case to SAAMI specs, then fired in the oversized (long) chamber. With best practices, other weaknesses (primer pockets, neck splits, etc.) will typically rear their head before casehead separation.

To the original question, rifle reloading involves considerably more case prep and inspection, but the actual reloading is same/similar. The greater forces, surface contact and die material does necessitate lubricating the case when resizing as mentioned above.

[MongooseV8]

I currently own at least 10 barrels with Ackley chambers, and have fire-formed roughly 80 bajillion pieces of brass.

But I have never once fired a round that shrank a case? I admit certain forum members routinely write posts that baffle my little brain. You could almost describe it as nonsensical.

[ar15barrels]

But I have never once fired a round that shrank a case?

Measure the overall length of a full length sized and deprimed case.

Then load the case and fire it.
Measure the length of the fired case after depriming but NOT resizing it.

The case gets reformed to fill the chamber when fired.
The brass required to fill the chamber is pulled into the case body from the neck.
It's normal that the case will get shorter after being fired.

Measure that same case again after depriming and fulll length re-sizing and it will be longer then when it was fired.
When you re-size the case, the brass flows back out of the body into the neck.

[fguffey]

You could almost describe it as nonsensical.

As opposed to logical: Some reloaders claim the rifle will blow up if it has too much head space, I say it has more to do with too much clearance, I do not say too much clearance will results in case head separation; I say there is more than one answer. If too much clearance causes case head separation I can check the rifle before pulling the trigger.

A builder called and (almost) accused me of causing him to have 5 case head separations out of the first 10 rounds he fired. I told him I could have checked his new build for the possibility of case head separation before he left the shop, I told him I could have met him at the range and fixed the problem before he attempted to fireform his cases.

If that seems nonsensical' it is OK.

F. Guffey

[Divernhunter]

^^^You either like to argue or just hear yourself talk.
Let it go

Have a nice day

[fguffey]

Have a nice day

Thank you, I will assume you have no clue about what is about to happen when you pull the trigger.

Before I pulled the trigger on the case with .127 clearance I knew the pressure was going to be low and I knew the case would be ejected with a very short neck and a long case body.

F. Guffey

[fguffey]

I knew the case would be ejected with a very short neck and a long case body

.

And I will say there is no one on this forum that can tell me "as opposed to what".

F. Guffey

[bsumoba]

Thank you, I will assume you have no clue about what is about to happen when you pull the trigger.

Before I pulled the trigger on the case with .127 clearance I knew the pressure was going to be low and I knew the case would be ejected with a very short neck and a long case body.

F. Guffey

Before I pulled the trigger on the case, I knew the case would ignite smokeless powder and a mass of copper and lead would shoot out the barrel and hit a target. And then there is the story about how bullets are held in the case with bullet hold

[ar15barrels]

Before I pulled the trigger on the case with .127 clearance I knew the pressure was going to be low and I knew the case would be ejected with a very short neck and a long case body.

there is no one on this forum that can tell me "as opposed to what".

How it started.

[fguffey]

Before I pulled the trigger on the case, I knew the case would ignite smokeless powder and a mass of copper and lead would shoot out the barrel and hit a target. And then there is the story about how bullets are held in the case with bullet hold

The questions was: What if the case had been ejected with a normal length neck/complete with the shoulder of the case connected?

And then there is the point that is beyond the ability of anyone on this forum to comprehend. The cases I fired with .127" clearance did not suffer case head separation. Reloaders claim excessive head space causes case head separation; I had .127" excessive head space -.005" for normal clearance.

I always check the length of the chamber from the shoulder to the bolt face on new purchases and builds. One method I use goes all the way back to Elmer Keith. If Elmer Keith was sensitive he would not have lasted as long as he die. Other smiths did not know how Elmer measured chambers and it was below their station to ask.

F. Guffey

[JagerDog]

The questions was:
F. Guffey

Ummmm....NO.